Recently, there have been developments in the field of wood processing in order to automate the various processes involved therein. More particularly, it has become more prevalent to optimize planers, and to automate wood grading stations.
In this context, automatic grading systems using linear scanner need a method to identify each board and retrieve board data down the line on the lug chain. Previously, when a board is scanned, an identification code is printed on the board, which is read later on the lug chain with a machine adapted to read the code, the code is then used to retrieved the grading decision previously saved.
One of the disadvantages of such systems is that the code so printed on the piece of wood takes up too much space, or is printed with a large quantity of ink. This results in an unsightly mark, which will not come off. Alternative embodiments have used UV ink to print the code, but the UV ink has a tendency to fade to yellow in time, again resulting in unsightliness.
Finally, since the code must be printed on the piece of wood at high speeds, it can result it sloppy marks, which are unreadable by the code reading apparatus.